There exists a class of devices for accessing fluid spaces and vessels within a human (or animal) body that are generally referred to as “ports”. Herein, “vessel” is defined as any conduit carrying a fluid within the patient's body. These prior art port devices generally comprise a chamber having an access opening sealed by means of a septum and having an egress from a second location leading to a catheter which is disposed within a fluid space or vessel. The septum allows a hollow needle (or “cannula”) to pass into the port's chamber, but then closes when the needle is removed, thereby preventing fluid leakage from within the bodily fluid space or vessel and also preventing anything from entering or exiting the port's chamber. These port devices are usually implantable below the skin so as to prevent infection, other contamination and mishandling.
A problem associated with prior art port devices is that they tend to have a somewhat irregular external shape. This can create various problems. For one thing, it can make it harder for the body to form a fibrin pocket about the port after the port has been installed below the skin. Furthermore, when the port has been deployed in the body for a prolonged period of time, the irregular external shape of the port can cause undesirable tissue erosion.
Another problem associated with prior art ports is that it can be difficult for medical personnel to locate a port beneath the patient's skin. Additionally, even after being located, it can be difficult for medical personnel to identify the orientation of the port within the body. This makes it more difficult for the medical personnel to find the port's needle (or cannula) entrances.
Still another problem associated with prior art ports is that, even after knowing the orientation of the port within the body, it can be difficult for medical personnel to insert the hemodialysis needles (or cannulas) in the needle (or cannula) entrances. In many cases, medical personnel strike the adjoining casing of the port, or pass the needle beneath the port.
Yet another problem associated with prior art ports is that it can be difficult to connect and disconnect catheters to the ports. For one thing, it can be difficult to securely lock the catheters to the ports. And, once locked, it can be difficult to thereafter unlock the catheters from the ports. In addition, some new catheters use coil-reinforced constructions. Such coil-reinforced catheters can be incompatible with prior art ports.